Capacitive sensors can be used to detect various physical quantities such as proximity, position, pressure, and acceleration, among other physical quantities based on capacitive coupling effects between electrodes. Capacitive sensors are present in several products including audio/video players, computer monitors, laptop trackpads, mobile telephones, vehicles, etc.
The physical scale of capacitive sensors can be reduced in order to increase their sensitivity. For instance, the sensitivity of capacitive sensors can be increased by reducing the distance between capacitive sensing electrodes. However, reducing the distance between capacitive sensing electrodes can lead to a reduction in the signal to noise ratio (SNR) associated with capacitive sensors due to a corresponding increase in parasitic capacitance either between sensing electrodes or from sensing electrodes to ground.